A stroke is a brain attack – a sudden interruption of blood flow to part of the brain causing it to stop working and eventually damaging brain cells. The effects can be devastating and may last a lifetime. A stroke is also known as a cerebrovascular accident (CVA).

There are several different types of stroke, with different causes.

Ischaemic stroke: This is the most common type of stroke, particularly in older people. An ischaemic stroke occurs when a clot blocks an artery in the brain. The clot usually forms in a small blood vessel inside the brain that has become narrowed through high blood pressure, high cholesterol, diabetes or smoking.

Embolic stroke: This occurs when a blood clot or piece of plaque (cholesterol or calcium deposits) on the wall of an artery breaks loose and travels to the brain. When this happens, the flow of oxygen-rich blood to the brain is blocked and tissue is damaged or dies.

Haemorrhagic stroke: This occurs when an artery in the brain ruptures (bursts) and leaks blood into the brain (cerebral haemorrhage). This break in the blood pipeline means parts of the brain are deprived of blood and a stroke occurs. Blood irritates brain tissue, causing swelling and pressure, which cause further damage and loss of function. Subarachnoid haemorrhage (SAH) is when blood leaks into the surface of the brain. Intracranial haemorrhage (ICH) is when there is bleeding into the brain tissue itself.

What are the risk factors for a stroke?

People of all ages can suffer a stroke but 75 percent happen in people over 65. Ischaemic strokes are the most common strokes in older people while younger people are more likely to suffer a haemorrhagic stroke. Most subarachnoid haemorrhages occur in people under 65.

In New Zealand, Māori and Pacific Islanders are more likely to suffer a stroke. Men are more likely than women, although pregnant women have a heightened risk.

TIAs are often called ‘mini strokes’. The symptoms are very similar to those of a stroke but the affects are usually temporary, lasting less than 24-hours. Most people who have TIAs fully recover within a few minutes or an hour.

Common symptoms may include:

sudden weakness and/or numbness of face, arm and/or leg especially on one side of the body

If you suspect you have had a TIA seek medical attention immediately. Never ignore the symptoms even if you fully recover. It might be a warning of a future more severe stroke, which could be prevented with treatment.

The signs and symptoms of stroke usually come on suddenly. The type of symptoms experienced will depend on what area of the brain affected. Strokes in the left side of the brain affect the right side of the body. A stroke in the right side of the brain results in signs and symptoms on the left side of the body.

Common first symptoms of stroke include:

sudden weakness and/or numbness of face, arm and/or leg especially on one side of the body

A stroke can cause permanent loss of function. Just what functions will be affected and how badly depends on what part of the brain the stroke was in and the speed and success of treatment. Strokes in the left side of the brain affect the right side of the body. A stroke in the right side of the brain results in signs and symptoms on the left side of the body.

Common long-term effects include impaired vision or speech, severe weakness or paralysis of limbs on one side of the body, swallowing difficulties, memory loss, depression and mood swings.

What is the treatment for stroke?

Prompt treatment increases the chances of survival from stroke and improves the likelihood of recovery.

Initial treatment is aimed at limiting the size of the stroke and preventing further strokes. First-line treatments commonly include medication and, in some cases, surgery to repair a ruptured blood vessel or remove a clot.

Long-term treatment involves supporting the brain to recover and for surviving brain cells to take over the functions of cells that have died or been damaged. This means the brain has to readapt and re-learn various skills. Recovery can take weeks and months supported by tailored rehabilitation plans developed in conjunction with the patient, their family and healthcare team.

Rehabilitation may involve:

physiotherapy

speech therapy

occupational therapy

Other health issues that may have contributed to the stroke, such as high blood pressure, heart rhythm problems or lifestyle behaviours are also targeted.

Sometimes the damage is permanent and the patient must learn to live with lifetime loss of function.

What will happen to me after I've had a stroke?

A person with a suspected stroke is usually admitted to an acute medical ward or specialised stroke unit for initial testing and treatment. Later they may be transferred to a rehabilitation ward or a separate stroke rehabilitation unit.

Some people with quite mild strokes may have initial tests at the hospital and then can go home. The hospital team organises ongoing therapy, which the person will have either as an outpatient or in their home.

When a person with stroke leaves hospital they will be encouraged to do activities without the physical assistance of a therapist as much as possible. This is called a self-directed, home-based rehabilitation programme. The rehabilitation therapist will be in touch regularly to check progress.

How long a person stays in hospital depends on many factors including the speed of recovery from the stroke, how independent the person was before their stroke, how much support they have at home, how appropriate their house is for someone with a disability and how bad the stroke is.

In a small number of cases, people with a stroke are unable to return home and will need long-term care in a private hospital or rest home.

What can I do to help prevent a stroke?

You can greatly reduce your chance of having a stroke by controlling risk factors. Strokes are usually the result of a combination of factors that have been present or developing for a long period of time. If someone has two or more known stroke risk factors the chances of having a stroke can dramatically increase.

By learning to recognise the symptoms of stroke you could save a life!

Stroke is a medical emergency. Call 111 immediately if you find yourself – or see anyone else – experiencing any of the above symptoms. Not all strokes are sudden and incapacitating. The sooner medical attention is received, the less damage a stroke will cause.